6.0.7 release

• Global
  • Removed VersionEye badge 😭 (@Geolim4)
  • Added VersionEye mention to credits (@Geolim4)
  • Added comprehensive changelog (@Geolim4)
  • Added tests against php 7.2 (@Geolim4)
  • Updated CREDITS.txt to markdown file (@Geolim4)
  • Updated EVENTS.md (@Geolim4)
  • Added OPTIONS.md (@Geolim4)
• Core
  • Fixed #529 // Memory leak caused by item tags (@Geolim4)
• Tests
  • Fixed hhvm build with subprocesses (@Geolim4)
  • Added test for option "itemDetailedDate" (@Geolim4)